2661421161 has 16 divisors (see below), whose sum is σ = 4060120064. Its totient is φ = 1519079184.

The previous prime is 2661421141. The next prime is 2661421177. The reversal of 2661421161 is 1611241662.

It is not a de Polignac number, because 2661421161 - 2⁶ = 2661421097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2661421141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53221 + ... + 90306.

It is an arithmetic number, because the mean of its divisors is an integer number (253757504).

Almost surely, 2^2661421161 is an apocalyptic number.

2661421161 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2661421161 is a deficient number, since it is larger than the sum of its proper divisors (1398698903).

2661421161 is a wasteful number, since it uses less digits than its factorization.

2661421161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144420.

The product of its digits is 3456, while the sum is 30.

The square root of 2661421161 is about 51588.9635581100. The cubic root of 2661421161 is about 1385.8126942360.

The spelling of 2661421161 in words is "two billion, six hundred sixty-one million, four hundred twenty-one thousand, one hundred sixty-one".